The 34-year-old DeSantis has the BRCA2 gene mutation, giving her a 40 percent to 60 percent chance of developing breast cancer by age 70, according to the Susan G. Komen Foundation, a breast cancer advocacy group. For BRCA1 carriers, like Jolie, the chances of getting breast cancer range from 40 percent to 87 percent. Women in the general population have about an 8 percent to 12 percent chance of developing breast cancer.

Doctors, counselors and nurses who specialize in breast cancer say they are seeing more women with genetic mutations turn to mastectomy as a way to prevent the disease. It can be a controversial topic that draws criticism from some who think removing both breasts goes too far. But women who go through with the procedure say they are driven by a need for stability in their life, a way to stop the constant worrying of when they might develop cancer. They want to live to watch their kids grow up and have families of their own.

"To me it was not a hard decision," DeSantis said. "I felt better knowing because I knew there was something I could do about it."

DeSantis began constantly worrying about developing breast cancer in her 30s. Her mother first developed the disease when she was 38, and eventually died from it. Her grandmother also died from the disease. DeSantis fretted that it might be her fate as well if she didn't do something drastic.

"There has been a lot of breast cancer in my life, and I was not prepared to die from that," DeSantis said.

Jolie, whose mother died from ovarian cancer at 56 and never met most of her grandchildren, also wanted to better ensure a longer life. In an opinion piece in The New York Times on Tuesday, the actress wrote that her risk of developing cancer is now 5 percent.

"I can tell my children that they don't need to fear they will lose me to breast cancer," Jolie wrote.

A woman's choice to have a double mastectomy before she develops cancer is one that does not come easily for many. Doctors say it is a very personal decision.

First, women have to decide, with the help of a doctor, whether they should be tested for a gene mutation. Doctors recommend that women should get the gene mutation test if they have long family histories of breast cancer, a male family member who has had breast cancer or a family member under age 45 who has had breast cancer. Those who are of Ashkenazi Jewish heritage and have a family history of breast or ovarian cancer also should be tested because they have a high incidence of breast cancer.

Some don't want to take the test because they fear the results.

Many doctors recommend genetic counseling, in which patients talk about how they might feel if they test positive for a gene mutation. They also explore what they might do if they test positive, asking whether they would consider a mastectomy or do more screenings.

"A woman might not always know for sure what they would do in the situation," said Jessica Rispoli Joines, a certified genetic counselor with the University of Maryland Medical System. "But there is value in making sure a woman knows of all the options there would be."

Counselors say they don't want a woman to think about the options right after a mutation diagnosis when they may react out of fear.

"The decision should not be done in haste," said Lillie Shockney, administrative director of the Johns Hopkins Breast Center. "Women need to understand that, though it will certainly reduce the risk, some women will mourn the loss of their breasts to the point that they get clinically depressed. On the other hand, some people are so petrified of getting the disease, they are better off getting a mastectomy."

There are options for those women who decide a double mastectomy is too drastic. While it is the most effective prevention method, women can also choose to get more screenings or turn to hormone-blocking drug therapy.

"There is no one right answer for everyone," said Dr. Kristen Fernandez, director of the Breast Center at MedStar Franklin Square Medical Center in Baltimore. "This has to be a thought-out discussion between the woman and doctor. It shouldn't be a rash decision made easy. It shouldn't be one made out of fear."

Jolie said she shared her experience to bring attention to the issue.

"I chose not to keep my story private because there are many women who do not know that they might be living under the shadow of cancer," she wrote. "It is my hope that they, too, will be able to get tested, and that if they have a high risk they, too, will know that they have strong options."

Women with those gene mutations also need to consider getting their ovaries removed because they also have a high risk for ovarian cancer, a disease that is hard to detect. Some women wait until after they have children and are closer to menopause to do this. Jolie said she started with her breasts because it is a more complex operation. She didn't say if she would eventually have her ovaries removed.

Cheryl Corbin, who had a double mastectomy in the 1990s, said Jolie's experience has the potential to help women around the world.

"As much as I hate that Angelina Jolie had to go through this, I am so happy that someone who is so high-profile, who has such a voice worldwide, can tell her experience firsthand," Corbin said.

Corbin, project manager for the University of Maryland Women's Health clinic, discovered she had a gene mutation after an oncologist suggested she get tested because her mother and grandmother had breast cancer.

She had a hunch the test would return positive. "I just have too much cancer in my family," she said. While she waited for the results, she had decided on a double mastectomy.

"In my own mind, I needed to get rid of my breasts," she said.

Corbin said the double mastectomy was the best decision she could have made. A doctor said there were precancerous cells in her breast tissue and she would have likely developed cancer in a few years.

With nearly 200,000 people diagnosed each year as having breast cancer, the disease touches many of us. Here are a few celebs who can count themselves as survivors. Check out our breast cancer page, too.

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